And each side gets only a handful of dismissals. You waste it on some guy you think is "too smart" and you might not be able to use it on that guy who thinks your client is guilty already.
Not a lawyer but I think you have unlimited dismissals [1] its just there's a limit to the number of ones you don't have to provide a reason for. And I'm also sure the rules vary state by state.
[1]: https://www.americanbar.org/groups/public_education/resource...
So the “no questions asked” dismissals tend to be people who may be sympathetic to either side.
If it’s a murder case the defense may want people who are pro-self defense while the prosecution may not.
Being pro or anti-self defense isn’t in itself a disqualified as long as you can follow jury instructions.
Wouldn't one side having a 49% chance be enough for them to prefer the coin flip?
Lawyer: Are members of your profession stereotypically capable of independent critical thought?
Juror: Yes?
Lawyer: Dismissed.
(They just ask for professions and maybe educational background then infer the rest.)